Thanks!
Update: I had put some MTS in when I added the betta the first day at work, but they were all dead by the end of the week (were all sitting exactly where they fell by the end of the 2nd day, couple had been moving about on sand/glass prior) as well as the zebra nerite that had been moving some the first day. At first I thought perhaps I had disturbed them too much from rearranging the tank or perhaps the temp fluctuation might have done them in. Now, I'm a little concerned that the pipes in the building might be copper or partly copper because I had taken all the dead snails out last week before I left for the weekend. Yesterday, I added some that I had made sure were moving before plucking them out of the 75g at home (first time just grabbed whatever I stirred up) with a variety of large to very small ones. They were moving about, but now I don't see any movement. Some must've buried themselves, but 2 of the large ones have sat in the same place since yesterday morning, and I see some small ones on the surface as well (not sure if they have moved). I'm gonna bring in my copper test tomorrow if I remember and test before bringing in any more inverts! Yikes! I'd been hoping to have a red spot nerite from Mgamer (Bob's Tropical Plants.com), but now I'm glad I had him send to my house instead of to work where the betta is! Crisis averted, for now.
I added a couple rocks, one is quartz/granite with a Windelov Java fern tied to it. The other two I'm not sure what they are but one looks to have some quartz in it and is mostly pink/brown. The other is 1/3 white and 2/3 light gray, really neat against the black sand.